DS1321S/T&R Maxim Integrated Products, DS1321S/T&R Datasheet
DS1321S/T&R
Specifications of DS1321S/T&R
Related parts for DS1321S/T&R
DS1321S/T&R Summary of contents
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FEATURES § Converts CMOS SRAM into nonvolatile memory § Unconditionally write-protects SRAM when V is out of tolerance CC § Automatically switches to battery backup supply when V power failure occurs CC § Flexible memory organization - Mode 0: ...
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DESCRIPTION The DS1321 Flexible Nonvolatile Controller with Lithium Battery Monitor is a CMOS circuit which solves the application problem of converting CMOS SRAMs into nonvolatile memory. Incoming power is monitored for an out-of-tolerance condition. When such a condition is detected, ...
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MEMORY CONFIGURATIONS The DS1321 can be configured via the MODE pin for three different arrangements of the four attached SRAMs. The state of the MODE pin is latched at V MEMORY CONFIGURATIONS Figure 1 MODE = GND (4 BANKS WITH ...
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BATTERY VOLTAGE MONITORING The DS1321 automatically performs periodic battery voltage monitoring at a factory-programmed time interval of 24 hours. Such monitoring begins within t when power failure occurs. After each 24-hour period (t resistor (R ) for one second (t ...
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FRESHNESS SEAL MODE When the battery is first attached to the DS1321 without V immediately provide battery-backup power on V leave Freshness Seal Mode. This mode allows a battery to be attached during manufacturing but not used until after the ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the ...
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CAPACITANCE PARAMETER Input Capacitance ( *, TOL, MODE) CEI Output Capacitance ( *, , ) CEO BW RST AC ELECTRICAL CHARACTERISTICS PARAMETER to Propagation Delay CEI CEO Pulse Width CE V Valid to End of CC Write Protection V Valid ...
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TIMING DIAGRAM: POWER-UP NOTE > will begin to slew with V BAT CCTP CCO when CCI CCI CCTP ...
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TIMING DIAGRAM: POWER-DOWN NOTES > will slew down with V BAT CCTP CCO until CCI CCI CCTP ...
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TIMING DIAGRAM: BATTERY WARNING DETECTION NOTE measured from the expiration of the internal timer to the activation of the battery warning output TIMING DIAGRAM: BATTERY REPLACEMENT ...
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NOTES: 1. All voltages referenced to ground. 2. Measured with outputs open circuited the maximum average load which the DS1321 can supply to attached memories at V CCO1 V -0.2V. CCI the maximum average ...
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DATA SHEET REVISION SUMMARY The following represent the key differences between 03/26/96 and 06/12/97 version of the DS1321 data sheet. Please review this summary carefully. 1. Changed I from 200 to 185 mA max CCO1 2. Changed I from 350 ...